Modeling Axial-Shear-Flexure Interaction of RC Columns for Seismic Response Assessment of Bridges

             Jian Zhang, Ph.D.
             Associate Professor
             Department of Civil and Environmental Engineering
             University of California, Los Angeles
             时间：2012年9月12日下午3:30-5:30
             地点：同济大学土木大楼B504
             主持人：吕西林 教授
 

Abstract

This seminar will discuss: 1) key model developments for accurately and realistically assessing the seismic responses of bridge columns under combined actions of axial force, shear force and bending moments; 2) a simple demand model for estimating the inelastic displacement and ductility of bridge columns considering shear-flexural interaction; and 3) effects of the axial-shear-flexure interaction (ASFI) on system level responses of bridges. Two coupled hysteretic models were developed, calibrated and implemented in a displacement-based finite element framework. Comparing with a large number of experimental cases, the developed models can accurately capture the pinching, stiffness softening and strength deterioration of columns due to the combined loads. These models also allow for efficient seismic response assessment of bridges. By evaluating the seismic responses of several prototype bridges with different structural characteristics, it is demonstrated that the ASFI effects can increase the seismic displacement demands of bridges under multi-directional ground motions.

Biographical Sketch

Dr. Jian Zhang is an Associate Professor in the Department of Civil and Environmental Engineering at the University of California, Los Angeles. In December 2002, she received her Ph.D. degree in Civil Engineering from University of California at Berkeley with a major in Structural Engineering and minors in Mechanics and Mathematics. Before joining UCLA in July 2005, she worked as an Assistant Professor at University of Illinois, Urbana-Champaign from 2003-2005. She was the recipient of the 2009 Northrop Grumman Excellence in Teaching Award from UCLA. She was also a JSPS Short-term Invitation Fellow from Japan Society for the Promotion of Science (JSPS) in 2003. She currently serves as an Associate Editor for ASCE Journal of Bridge Engineering, Chair of ASCE/SEI Performance-Based Design for Structures committee, Vice Chair of ASCE/SEI Structural Control committee. She is a current member of American Society of Civil Engineers (ASCE), Earthquake Engineering Research Institute (EERI), Consortium of Universities for Research in Earthquake Engineering (CUREE), Network for Earthquake Engineering (NEES), ASCE/SEI Seismic Effects Committee, NEEScomm Simulation Steering Committee and ASCE/SEI Emerging Analysis Methods in Earthquake Engineering Subcommittee. She routinely serves as a reviewer for prestigious journals in structural/earthquake engineering including Earthquake Engineering and Structural Dynamics, Soil Dynamics and Earthquake Engineering, Journal of Structural Engineering, Structural Control and Health Monitoring and Journal of Engineering Mechanics etc. and a reviewer for federal funding agencies in U.S.

Dr. Jian Zhang’s research interests are earthquake engineering, structural dynamics and mechanics, with an emphasis on the modeling, analysis and protection of structural systems under extreme loads. Her recent research activities include fragility functions of highway bridges due to seismic shaking and liquefaction induced lateral spreading, soil-structure interaction effects, axial-shear-flexural interaction of reinforced concrete columns, seismic protection using adaptive stiffness and damping devices and performance-based earthquake engineering. Her research work has been supported by National Science Foundation (NSF), California Department of Transportation (Caltrans), and Pacific Earthquake Engineering Research Center (PEER). She has published over 70 technical papers and reports, including 22 SCI indexed journal papers that are well cited.